1. Field of the Invention
The present invention relates to fruit processing machinery and specifically to a papaya scraping or peeling machine.
2. Description of the Prior Art
Papaya puree was traditionally produced by chopping the whole fruit and screening the pulp out from the skin and seeds. However, that process yielded bitter tasting puree. It is preferable to peel the skin off and remove the seeds unbroken. As hand-peeling is laborious there has been a need to mechanize the process, which is difficult because the more regularly shaped papayas are sold fresh leaving irregular shapes for puree production. A papaya scraper built by Angara et al. was described in the December 1969 issue of the Transactions of the American Society of Agricultural Engineers at pp. 745-751. It comprised two feeder belts, a puree collection hopper, and a rotating scraper drum holding alternating round rods and wedge-shaped blades parallel to its axis. Papayas were sliced into thirds and placed face down on the first belt, which carried them to the downward-facing second belt. Friction of the second belt held the papaya skin as the flesh and seeds were scraped away by the drum and deposited in a puree collection hopper. The momentum of the skins carried them beyond the collection hopper. That machine was modified as described by Brekke et al. in Research Bulletin 170 of the Hawaii Agricultural Experiment Station at the University of Hawaii. The modified machine used all round rods, to reduce seed breakage, but the pulp and seeds were only loosened from the skins, and had to be separated later by a centrifuge. Because papaya skins contain bitter tasting latex, steaming or "blanching" the whole fruit before processing was necessary to coagulate the latex and prevent it from exuding from cuts in the skin while the skins were mixed with the pulp.
The supply of and demand for papaya puree have continued to increase, for example in Costa Rica, making necessary a more satisfactory peeling machine.